PLATE LXXI 
Ordovician, Silurian 
Devonian { 
== Lower/Nssissizcian\ 
BSSS&erzer ” 
MMM evnsylvariiari 
Cretaceouslertiary 
[1 Quaternary 
09 SOK ETT? LINMTE OC. 
Glaciatior 
fora T7af? OF The 
Lils Geol Survey. 
ood se ses: 
"00, 
S00 
'o, 
©9966 
"9000 
